In facsimile (fax) transmissions, data is encoded for transmission over telephone lines or radio broadcast for print out at a remote location.
When performing a fax transmission, after making a connection with a receiving fax machine, a transmitting fax machine scans an image including, for example, text and/or graphics, by reading a very small area of the image at a time. The fax machine decides whether the area read is light or dark and digitizes the area by assigning the area a number such as “0” for white and “1” for dark. Then the fax transmits the number to a remote facsimile receiver. The receiver, for example, prints out the received image on a print media. This process continues as the transmitting machine scans a series of small areas horizontally across the image, and transmits that information to the remote receiver. The transmitting fax then scans a next lower line and so on until the entire image has been scanned, digitized, and transmitted.
As fax machines have increased in popularity, features have been added to fax machines to make them more versatile and convenient. For example, some fax machines have the ability to scan and transmit color images. Some fax machines include auto-dialing and fax number storage. There is a continuing quest to improve fax machines by increasing their versatility and convenience of use.